Network providers may offer virtual private networks (VPNs) to their customers. Using a VPN, a customer may be able to communicate confidential information over a public or shared network. A network provider may implement a VPN over a private network using MultiProtocol Label Switching (MPLS). MPLS is a data-carrying protocol that may provide the features of a circuit-switched network over a packet-switched network. MPLS may carry many different kinds of traffic, including internet protocol (IP) packets, as well as asynchronous transfer mode (ATM), synchronous optical network (SONET), and Ethernet frames.